In a vote of 55-45, the Senate passed the Iran War Powers Resolution on Thursday afternoon, setting out opposition to any unauthorized war with Iran, and instructing the president not to deploy troops for such a war.
Voting was heavily along party lines, with Democrats and some antiwar Republicans managing to pass the resolution in the face of mocking opposition from the Republican leadership, who insisted the resolution could never survive a Trump veto, and was a sign of weakness against Iran.
The Senate Republicans supporting were Mike Lee of Utah, Rand Paul of Kentucky, Susan Collins of Maine, Todd Young of Indiana, Jerry Moran of Kansas, Lamar Alexander of Tennessee, Bill Cassidy of Louisiana and Lisa Murkowski of Alaska.
Trump has opposed the resolution, arguing overwhelming support for his recent hostility toward Iran. Trump has broadly opposed war powers challenges to his wars, arguing he is allowed to launch such conflicts without Congress.
A veto has the potential to be overridden in the House, but it so far looks unlikely that the Senate could do so. That may ultimately depend on growing opposition to the war by the time the override happens.